The present invention relates to roof retrofitting, that is, replacing an existing roof with a new roof and, more particularly, relates to a base sheet for use in such retrofitting.
In the past, in order to retrofit certain types of roofs, such as gravel surfaced roofs, it has been necessary to either scrape the roofs smooth or lay a relatively rigid insulation or recovery board over the roof. Either of these approaches has proven to be time consuming and costly. In addition, when the roof is not scraped clean, the presence of gravel under the new roof can sometimes be visually apparent thereby impairing the aesthetics of the roof.
It is an object of the present invention to retrofit new roofing to existing roofing in a faster, more economical and more efficient manner without impairing the aesthetics of the new roofing.
The foregoing and other objects of the invention are achieved by employing a base sheet which includes a layer of flexible foam laminated to a support sheet.
The flexible foam cushions the underlying gravel, thus, preventing it from cutting through the new roofing and causing any leakage. Further, the flexible foam drapes over the gravel hiding it from sight, thereby resulting in a more aesthetic roof.